Semiconductor devices are used in a variety of electronic applications, such as personal computers, cell phones, digital cameras, and other electronic equipment. Semiconductor devices are typically fabricated by sequentially depositing insulating or dielectric layers, conductive layers, and semiconductive layers of material over a semiconductor substrate, and patterning the various material layers using lithography to form circuit components and elements thereon.
Lithography processes are widely used to form photoresist layers on semiconductor wafers. Lithography processes include hot baking processes to solidify the photoresist layers. In the hot baking processes, a wafer with a photoresist layer is disposed on a hot plate and heated by the hot plate.
However, during the hot baking processes, some particles are formed by the photoresist and deposited on the hot plate. When a subsequent wafer is placed on the hot plate, the particles deposited on the hot plate may be raised and then fall on the wafer, and therefore the wafer becomes contaminated by the particles. Therefore, there are challenges to minimizing particulate contamination of the wafers during processing.